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Aim This study evaluated new bone formation activities and trabecular bone microarchitecture within the highly porous region of Trabecular Metal™ Dental Implants (TM) and between the threads of Tapered Screw‐Vent® Dental Implants (TSV) in fresh canine extraction sockets. Materials and methods Eight partially edentulated dogs received four implants (4.1 mmD × 13 mmL) bilaterally in mandibular fresh extraction sockets (32 TM, 32 TSV implants), and allowed to heal for 2, 4, 8, and 12 weeks. Calcein was administered to label mineralizing bone at 11 and 4 days before euthanasia for dogs undergoing all four healing periods. Biopsies taken at each time interval were examined histologically. Histomorphometric assay was conducted for 64 unstained and 64 stained slides at the region of interest (ROI) (6 mm long × 0.35 mm deep) in the midsections of the implants. Topographical and chemical analyses were also performed. Results Histomorphometry revealed significantly more new bone in the TM than in the TSV implants at each healing time (p = .0014, .0084, .0218, and .0251). Calcein‐labeled data showed more newly mineralized bone in the TM group than in the TSV group at 2, 8, and 12 weeks (p = .045, .028, .002, respectively) but not at 4 weeks (p = .081). Histologically TM implants exhibited more bone growth and dominant new immature woven bone at an earlier time point than TSV implants. The parameters representing trabecular bone microarchitecture corroborated faster new bone formation in the TM implants when compared to the TSV implants. TM exhibited an irregular faceted topography compared to a relatively uniform microtextured surface for TSV. Chemical analysis showed peaks associated with each implant's composition material, and TSV also showed peaks reflecting the elements of the calcium phosphate blasting media. Conclusions and clinical implications Results suggest that the healing pathway associated with the highly porous midsection of TM dental implant could enable faster and stronger secondary implant stability than conventional osseointegration alone; however, prospective clinical studies are needed to confirm these potential benefits in patients with low bone density, compromised healing, or prior implant failure.

Objective The aim of the present 2-year follow-up study was to assess the effect of oral hygiene maintenance on hemoglobin Alc (HbA1c) levels and peri-implant parameters around immediately-loaded dental implants placed in type-2 diabetic patients with varying glycemic levels. Material and methods Ninety-one individuals were divided into three groups. In group 1, 30 systemically healthy individuals were included (HbA1c

Objective Bone grafts (sinus lift and/or ridge augmentation) may become an obstacle for some patients who desire implant treatment. The objective of this study was to evaluate the success of six- and eight-millimeters rough surface design short dental implants, for up to 2 years in function, when compared to conventional length (11 mm) implants. Materials and Methods A total of 25.6-, 20.8- and 35.11-mm length implants were placed and restored in 30 subjects (11 males, 19 females) between the age of 22 and 80, following a standard protocol. Implant mobility, crestal bone loss as well as periodontal parameters were evaluated immediately after restoration placement, at 6, 12 and 24 months. Results There was one failure of one 6-mm implant during the healing phase and one restorative failure. The median crestal bone loss at 24 months was 0.45 mm for the 6-mm implants, 0.55 mm for the 8 mm implants and 0.65 mm for the 11-mm implants. The success rate for 6-mm implants was 97% and for 8-mm and 11-mm implants 100%. Conclusions Based on this preliminary data, we conclude that rough surface design short dental implants (6 and 8 mm in length) have similar success rate when compared to 11-mm implants. Long-term data with larger number of implants and subjects are needed to confirm these results.

This is the peer reviewed version of the following article: Romanos GE, Delgado-Ruiz RA, Go mez-Moreno G, Lo pez- Lo pez PJ, Mate Sanchez de Val JE, Calvo-Guirado JL. Role of mechanical compression on bone regeneration around a particulate bone graft material: an experimental study in rabbit calvaria. Clin. Oral Impl. Res. 00, 2015; 1–8., which has been published in final form at [10.1111/clr.12592I]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. Purpose: This experimental study was designed to analyze the effect of different compressive forces on the bone regeneration around a particulate bone graft material. Material and methods: Eighty 6-mm-diameter defects were created in the calvaria of 20 New Zealand rabbits (4 defects per rabbit calvaria). All the defects were filled with particles of synthetic bone. Two standardized compressive forces were then applied, 4.1 g to half the defects (Test A) and 8.2 g to the other half (Test B), all for 1 min. The graft sites were allowed to heal for 6 weeks, after which the rabbits were euthanized. The calvarium vault of each animal was extracted, radiographed, and prepared for histomorphometric analysis. The percentage of defect fill, bone density, new bone formation, and residual bone graft material were recorded, and the results were subjected to statistical analysis. Results: Histological evaluation found that defect closure among the Test A (lower compression) group ranged from 38.34 (95% lower CI) to 55.8 (95% upper CI) (mean 47 8.5%), while among the Test B group (higher compression), it ranged from 81.26 (95% lower CI) to 95.32 (mean 88 7.3%). Significantly more closure was achieved for the Test B group (P < 0.05). Histomorphometric comparison of the two groups found significantly more new bone formation, higher bone density, and a higher percentage of defect fill in the defects subjected to the higher compression level (P < 0.05). Conclusions: Increasing the compressive force applied to bone graft particulate used to fill small defects created in rabbit calvaria appears to be beneficial. Odontología

Objective This study reports the characterization process and in vivo application of a new high-porosity biphasic calcium phosphate (4Bone® – HA 60%/β-TCP 40%) inserted into the critical size defect of a rabbit tibiae. Material and methods Two critical size defects of 6 mm diameter were created in each tibia of 15 New Zealand rabbits, and a total of 60 defects were divided into a test group filled with 4Bone® (n = 30) and a control group (n = 30). The material and the implants were characterized by scanning electron microscope (SEM) fitted with energy-dispersive X-ray spectroscopy (EDX). Results The biomaterial's grain size decreased progressively with the graft integration process over the 60-day study period. Element analysis revealed increased percentages of Ca/P (2.86 ± 0.32 vs. 1.97 ± 0.59) in new bone and at the interface (P

Objective The aim of this study was to assess the bone regeneration of critical size defects in rabbit calvarias filled with β-TCP doped with silicon. Materials and methods Twenty-one New Zealand rabbits were used in this study. Two critical size defects were created in the parietal bones. Three experimental groups were evaluated: Test A (HA/β-TCP granules alone), Test B (HA/β-TCP granules plus 3% silicon), Control (empty defect). The animals were sacrificed at 8 and 12 weeks. Evaluation was performed by μCT analysis and histomorphometry. Results μCT evaluation showed higher volume reduction in Test A group compared with Test B (P

This is the peer reviewed version of the following article: Romanos GE, Delgado-Ruiz RA, Calvo-Guirado JL. Influence of the implant diameter and bone quality on the primary stability of porous tantalum trabecular metal dental implants: an in vitro biomechanical study. Clin. Oral Impl. Res. 00, 2016, 1–7], which has been published in final form at 10.1111/clr.12792. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. Objectives: The aim of this study was to evaluate the primary, initial stability of Porous Tantalum Trabecular MetalTM implants (TM) compared with Tapered Screw Vent" implants (TSV) with different diameters, inserted in two bone densities. Methods: A total of 160 implants (80 TM and 80 TSV) with narrow (3.7 mm) and conventional (4.1 mm) diameters and the same length (10 mm) were placed in artificial bone blocks representing bone qualities II and IV. The implant stability was evaluated by insertion torque (IT) and Resonance Frequency Analysis. Statistical analysis was performed with non-parametric Kruskal– Wallis test with Dunn post-test for the differences between groups. Results: TheresultsshowedhigherISQvaluesindensebonecomparedwithsoftboneforallthe groups (P < 0.05). Conventional-diameter implants (TSV and TM) showed higher ISQ and IT values compared with narrow implants (TSV and TM) in dense and soft bone (P < 0.05). Tapered TSV implants showed higher stability in soft bone compared with TM implants (P < 0.05). In dense bone, differences were not observed between narrow TSV 3.7 mm and TM 3.7 mm implants (P > 0.05). Conclusions: Within the limitations of this study, it can be concluded: • In dense bone blocks, the wider diameter implants are more stable than narrow implants. • In soft bone blocks, the tapered TSV implants are more stable than TM implants. Odontología

OBJECTIVE We hypothesized that peri-implant soft tissue inflammation is worse and peri-implant marginal bone loss (MBL) is higher around dental implants placed in patients with prediabetes compared to healthy subjects. The aim of the present 12-month follow-up study was to compare the clinical and radiographic status around dental implants placed in patients with and without prediabetes. MATERIAL AND METHODS Twelve patients with medically diagnosed prediabetes (Group-1) and 12 controls (Group-2) were included. All patients were indicated for single tooth maxillary or mandibular premolar replacement with the adjacent teeth intact. Success of the restored implants was assessed by comparing clinical (peri-implant bleeding on probing [BOP], and probing pocket depth [PPD]) and radiographic (peri-implant MBL) parameters at baseline and at 12-months follow-up. Statistical analysis was performed using one-way analysis of variance, and P-values

Purpose The aim of this study was to evaluate the long-term clinical and radiographic outcomes of implants that were immediately loaded in a prospective, randomized, split-mouth clinical trial in the posterior mandible. Materials and methods Patients with alveolar ridges that were bilaterally edentulous distal to the canines were enrolled to participate. On one randomly selected side of each patient's jaw, three implants (control group) with platform switching and a progressive thread design were placed, allowed to heal for 3 months, uncovered, and loaded occlusally using resin-splinted crowns, which then were replaced 6 weeks later by final prostheses. Three additional implants (test group) of the same size and design were placed on the contralateral side of each patient in symmetrical locations. The test implants were connected to their final abutments immediately after placement and immediately loaded. Periodontal indices and bone loss were evaluated at regular intervals. Results After a mean loading period of 12.14 (±0.89) years for the test group and 12.40 (±0.89) years for controls, differences between the immediately and delayed loaded implants were not statistically significant (P > 0.05). The crestal bone loss was (mesial) 0.70 (±1.09) mm (test group) and 1.17 (±1.27) mm (control group) and the distal bone loss was 0.43 (±1.02) mm (test group) and 1.06 (±1.33) mm (control group) (P > 0.05). The maximum crestal bone loss was 3.12 mm for the test group and 3.78 mm for the controls after 10.125/10.397 years, respectively. Conclusion Immediate loading does not negatively influence the long-term prognosis of dental implants in the posterior mandible, improves the implant stability, and is associated with minimal crestal bone loss when platform switching and a one-abutment concept with a Morse-tapered connection are used.

To study the peri-implant bone organization pattern of immediately loaded (IL) zirconia implants with microgrooved surfaces.Forty-eight dental implants of 4 mm diameter and 10 mm length were inserted after two months postextraction healing in the edentulous mandible of six dogs. Three groups of sixteen implants were used, titanium implants (Control), zirconia implants (test A), and zirconia-microgrooved implants (test B), which were loaded immediately. After 4-month healing period, implant-bone samples were processed and analyzed by circularly polarized light (CPL) and confocal laser scanning microscopy (CLSM) in two regions of interest ROI1 (to evaluate the interthread bone) and ROI2 (to evaluate the bone adjacent to the threads) of 1 mm thickness × 10 mm length each one.Bone organization differs near to the test B, compared with test A and control surfaces, active remodeling was detected surrounding test B implants, with alternancy of organized zones, meanwhile controls and test A areas showed organized areas mainly at 2 mm of implant surfaces. Transverse collagen fibers were significatively higher at ROI1 for test B implants (60.34 ± 4.34%), compared with controls (47.25 ± 3.51%) and test A (43.78 ± 2.78%) groups (P0.05). Meanwhile, it was not found any significant difference between groups in ROI2 (P0.05). CLSM confirmed the presence of collagen mineralized matrix inside microgrooves of test B groups. 3D reconstruction showed blood vessels in direct contact with the implant surfaces of all groups and bone and blood vessels penetration inside the microgrooves in test B group.The organized pattern of the microgrooved surfaces is able to induce transverse collagen fiber microenvironment reaction to the load, being positive to promote and to maintain the bone remodeling; in addition blood vessels and bone cells are able to penetrate microgrooved surfaces.

Objective To carry out the histological and histomorphometric plus radiological analysis of biphasic ceramic. Materials and method In this study, porous HA/βTCP (4Bone(®) ) ceramic material was tested for the bone repairing capacity and osteoinductive potential in a New Zealand rabbit model. The ratio of the ceramic's components HA/βTCP was 60/40 (in wt%). Results The 4Bone(®) showed significantly more bone formation in the pores and in the periphery of the graft than the control group. Histomorphometric analysis revealed that the ceramic material (66.43% ± 0.29) produced higher values of bone-to-implant contact (BIC) percentages (higher quality, closer contact); moreover, defect closure was significative higher in relation with control group (64.15% ± 3.52). Conclusions 4Bone(®) is a biocompatible, partially resorbable and osteoconductive grafting material. Biphasic graft material of HA/βTCP with a porosity of 95% without loading favors new bone formation.

To perform a systematic review of studies that report the healing of critical size defects (CSDs) in rabbit calvaria and to determine the quality of the studies according to ARRIVE guidelines.An Internet search was made in duplicate between December 2011 and August 2013 using MEDLINE, PubMed and Google Scholar (without restrictions on date of publication) for rabbit studies reporting the healing of CSD in the calvaria. Animal Research Reporting in Vivo Experiment (ARRIVE) guidelines (a list of 20 aspects to score and to ensure comparison between different experimental studies in animals) were used to evaluate the quality of the selected works.Twenty-five manuscripts were evaluated. Case-control studies predominated (92.59%). Animal age was not stated in 70.37% of the studies; weight was not reported in 29.62%; most animals weighed 3.5 kg (26.31%). A CSD dimension of 15 mm was common (51.61%), generally located centrally (51.85%), followed by bilateral locations (48.14%). Circular (66.66%), rectangular (14.81%), square (14.81%) and ovoid (1.48%) geometries were used. Histomorphometric data showed incomplete healing in all CSDs and higher percentages of healing in smaller defects (10 mm). The longer the healing time allowed, the more bone healing took place, for both smaller and larger defects (15 mm). Minimum quality grades were assigned to ARRIVE items study design (6), experimental animals (8), housing and husbandry (9), sample size (10), allocation (11), statistics (13), results-baseline data (14), numbers analyzed (15), adverse events (17) and funding (20).Data on CSDs in rabbit calvariae lack homogeneity. Smaller defects can be considered critical depending on the time of sacrifice. When new diagnostic technologies are used in addition to histomorphometry, these should be applied with caution to facilitate future comparison with other research. The ARRIVE guidelines should be followed in any animal research protocol to improve the homogeneity, comparison and reproducibility between studies.

Purpose The aim of this study was to evaluate bone-to-implant contact after immediate implant placement at different levels in relation to crestal bone in American foxhound dogs. Materials and methods The mandibular second, third, and fourth premolars of six American foxhound dogs were extracted bilaterally. Randomly, three immediate implants were placed in the hemimandible of each dog at the bone crest (control group) or 2 mm subcrestally (test group). Three dogs were allowed an 8-week healing period; the other three were left a 12-week healing period. After healing periods, histomorphometric analyses of the specimens were carried out to measure BIC values and bone remodeling. Results All implants healed uneventfully and were available for histological analysis. The total BIC mean values were 44.52% (±8.67) and 39.50% (±9.25) at 8 and 12 weeks, respectively, for the control group, and 47.33% (±5.23) and 53.85% (±4.21) at 8 and 12 weeks after healing for the test group, respectively. There was observed less bone resorption in the group of implants placed subcrestally. Conclusion Our findings suggest that less resorption may be expected when implants are inserted 2 mm subcrestally. Moreover, higher BIC values in the group of subcrestal implants were found.

Objectives To evaluate a new hybrid drilling protocol, by the analysis of thermal changes in vitro, and their effects in the crestal bone loss and bone-to-implant contact in vivo. Materials and Methods Temperature changes during simulated osteotomies with a hybrid drilling technique (biologic plus simplified) (test) versus an incremental drilling technique (control) were investigated. One hundred and twenty random osteotomies were performed (60 by group) in pig ribs up to 3.75-mm-diameter drill to a depth of 10 mm. Thermal changes and time were recorded by paired thermocouples. In a parallel experiment, bilateral mandibular premolars P2, P3, P4, and first molar M1 were extracted from six dogs. After 2-month healing, implant sites were randomly prepared using either of the drilling techniques. Forty eight implants of 3.75 mm diameter and 10 mm length were inserted. The dogs were euthanized at 30 and 90 days, and crestal bone loss (CBL) and bone-to-implant contact (BIC) were evaluated. Results The control group showed maximum temperatures of 35.3°C ± 1.8°C, ΔT of 10.4°C, and a mean time of 100 s/procedure; meanwhile, the test group showed maximum temperatures of 36.7°C ± 1.2°C, ΔT of 8.1°C, and a mean time of 240 s/procedure. After 30 days, CBL values for both groups (test: 1.168 ± 0.194 mm; control: 1.181 ± 0.113 mm) and BIC values (test: 43 ± 2.8%; control: 45 ± 1.3%) were similar, without significant differences (P > 0.05). After 90 days, CBL (test: 1.173 ± 0.187 mm; control: 1.205 ± 0.122 mm) and BIC (test: 64 ± 3.3%; control: 64 ± 2.4%) values were similar, without significant differences (P > 0.05). The BIC values were increased at 90 days in both groups compared with the 30-day period (P